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    <meta charset="UTF-8">
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    <title>Document</title>
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<script>
    //首字母大写，使用forEach遍历
    var str = "no zuo no die";
    var arr = str.split(' ');
    var arr2 = [];
    arr.forEach(function(el,index,arr1) {
        var fistChar = el[0].toUpperCase();
        var newStr = fistChar + el.slice(1);
        arr2.push(newStr);
    })
    console.log(arr2.join(' '));

</script>
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